<?php
class Sb_Controller_Plugin_Auth extends Zend_Controller_Plugin_Abstract
{
	  public function routeShutdown(Zend_Controller_Request_Abstract $request)
	  {
	  		if(!Zend_Auth::getInstance()->hasIdentity( )){
	  			$request->setModuleName( 'default' )
	  							->setControllerName( 'auth' )
	  							->setActionName( 'login' );
	  		} 
	  }
}